The effects of lead on the behavior and development of offspring exposed chronically before and after birth are being studied. A broad battery of observations of physical developmental milestones, reflex ontogeny, and behavioral functions is being employed to determine the full range of neurotoxic potential of lead. These observations are being related to the teratogenic activity and body burden of lead as estimated from levels found in blood, brain, and bone at various times throughout the exposure period and to neurochemical parameters which indicate changes in developing brain chemistry. The value of this multidisciplinary approach will be evaluated in terms of its usefulness for routine evaluation of compounds with unknown neurotoxic potential.